The first car telephones connected to the Public Switched
Telephone Network in the United States were put into service in 1946, as a
response to the growing mobility of the American population in the postwar
years. Initial design of the mobile telephone itself was undertaken by the
Western Electric Corporation, the prime supplier of telephone sets to the
nation's Bell System operating companies, while Bell Laboratories itself
designed the overall system and set the specifications for the equipment.
At the same time, the independent telephone companies were developing their own
equipment, to be supplied by Automatic Electric. The Bell System equipment
built upon an already existing mobile radio set, Western Electric's 1945 vintage
Type 38 or 39 VHF FM police radio equipment, adding a telephone style handset
and a selective calling decoder, which rang a bell in the automobile when that
phone's unique number was signaled. The selective calling decoder consisted of a
small wheel in a glass enclosure, with pins located at certain points around its
circumference. The decoder had been developed in the 19th century for railway
right-of-way signaling, was later used in ship to shore radio telephone
installations in the 1930's, and was a proven concept. This decoder was
labeled "102." Western Electric and the Bell companies thus did not
draw up an entirely new concept for a car telephone in 1946; they used proven
components of other systems to create the new public car telephone service.

Mobile telephone equipment had already been in use
internally within the Bell System on an experimental basis, going back before
WWII, using mobile radios such as the Western Electric Type 28 VHF
equipment. One example was the Emergency Radiotelephone Service established by
New York Telephone in December, 1940, which used AM on the 30-40 Megacycle band.
Based on the successful tests of that equipment, AT&T announced the creation
of the General Mobile Radiotelephone Service on June 29, 1945, and applied to
the FCC for authority to establish base stations in Baltimore, Chicago,
Cincinnati, Milwaukee, Philadelphia, Pittsburgh, St. Louis, Washington DC,
Columbus Ohio, Denver, Houston, New York City, and Salt Lake City. One has
to wonder why nothing was initially considered for California.

The FCC and the Bell companies envisioned two forms of
mobile telephone service, "HIGHWAY" and "URBAN." Both would
be VHF, and both would use FM. The "Highway" service, as its name
implies, was intended primarily to serve the major land and water routes that
existed across the United States in the 1940's, which would not be served by the
"Urban" systems. Highway service was intended for trucks and barges on
inland waterways rather than private vehicles. Highway service was
allocated 12 channels in the VHF "low band," with the mobile equipment
receiving on 35 Megacycle and transmitting on 43 Megacycle frequencies, although
not all 12 channels were initially used. The Urban equipment, as its name
implies, was intended to serve mobile subscribers whose travels took them
primarily within the immediate radius of a major urban center, such as doctors,
delivery trucks, ambulances, newspaper reporters and so forth. Urban
equipment operated on VHF 152 Megacycles (receive) and 158 Megacycles
(transmit,) and the initial FCC allocation in 1946 was for 6 channels. The
separation in transmit and receive channels was necessary to provide a
"half duplex" communications circuit, and allowed the telephone
company base station to remain on the air continuously during the duration of
the call. The first Highway system went on the air in August 28, 1946 in Green
Bay, Wisconsin, and the first Urban system went on the air in Saint Louis on
June 17, 1946.

By 1948, Urban service was available in 60 cities in the
United States and Canada, with 4000 mobile subscribers, handling 117,000 calls
per month. Highway service was in place in 85 cities with 1900 mobile
subscribers, handling approximately 36,000 calls per month, with most major
highways in the east and Midwest covered.

The Bell System also entered the two-way business and
police radio market after the war by offering the rental of entire radio systems
including their maintenance and updating. This equipment was marked
"Bell System" either in white painted letters or with water-slide
decals. Smaller police departments were encouraged to use the
"Urban" mobile telephone system as opposed to a traditional dispatch
system, which must have been somewhat odd in operation. Most of the
equipment rented by the Bell System affiliates was Motorola two-piece
"Deluxe" equipment, FMTRU-5V "Dispatcher" and GE one-piece
pre-Progress Line radios. It is believed that the Bell System discontinued
this practice sometime in the early to mid 1950's.

Map of first "Highway" Mobile Telephone
Land Stations and channel assignments:

ORIGINAL URBAN SIX CHANNEL ALPHA-DESIGNATORS:

WJ WR JL JP JR JS

ORIGINAL HIGHWAY ALPHA CHANNEL DESIGNATORS:

ZF ZH ZM ZO ZB ZA
ZL

POST-NARROW BANDING ALPHA CHANNEL DESIGNATORS:

(After 1964)

Highway: ZO ZF ZH
ZM ZA ZY ZR ZB ZW ZL

Urban: JL
YL JP YP YJ YK JS YS YR JK
JR

UHF: QJ QA
QP QB QR QF QS QH QW QL QX QM

Typical installation of the first car
telephone:

WESTERN ELECTRIC 238 and 239
EQUIPMENT AND 41A CONTROL HEAD

The Western Electric house-made equipment
consisted of two pieces; the transmitter cabinet and the receiver cabinet. These
mounted in the automobile trunk, and a large cable brought forward under the
carpet connected to a "control head" under the dash which contained a
telephone handset. The control head featured two illuminated lenses--one
indicated that the equipment was turned on, and the other would illuminate when
the mobile telephone was called. The Western Electric Type 38 was Highway band
equipment, i.e. VHF low band, and the Type 39 equipment was Urban, or VHF high
band equipment. A complete installation would be prefixed "2"; in
other words, type 238 would be a complete Highway mobile telephone, and type 239
a complete Urban mobile telephone. As originally supplied, all equipment was
single channel in operation although two channel expansion was possible.

Transmitter shown below

The first Bell System mobile telephone control head was the Western
Electric Type 41A, seen below. The handset, with a cloth braided cord, stores in
a curious-looking spring loaded pocket on the bottom of the control head. The
bell and terminal strips for cabling are self contained in the 41A. There
were two styles of 41A control head; the difference was only in the faceplate
around the pilot lamps and toggle switch. The original 41A had two exposed
lamp lenses as shown. The later model had a smooth plastic sheet with
colored lens sheet pieces set behind it. The 41A set was technically a
single-channel installation although a multi-channel switch was developed which
mounted alongside in a separate box.

Type 41A Control Head with non-original rubber coiled
cord, a later replacement:

The equipment for decoding a ringing signal to a
particular car was a rotary stepper wheel with a latch, designed to count
inbound pulses as they were dialed from the land side station, located on a
chassis called the "Selector.". The land station's signal
consisted of alternating pulses of 600 and 1500 Hz tones representing the
various numbers. The description of how this worked is below. If all the
right numbers were received, the wheel would reach the end of its travel and a
bell would be activated either inside the control head (41 Series) or (later) in a bell
box under the car dash (47 Series.)

In 1949 a typical number scheme for the equipment was as
follows:

Transmitters

Type 38BUrban 6 Volt

Type 38CUrban12 Volt

Type 39AHighway 6 Volt

Type 39BHighway 12 Volt

WETU-30-DUrban Motorola Deluxe 6 Volt

WETU-30-12D Urban
Motorola Deluxe 12 Volt

In the type 38
and 39 receivers, the decoder circuitry was mounted inside the receiver chassis. Western Electric
also manufactured a separate housing for this decoder, such that it could be used
with other makes of mobile radio equipment, such as the Motorola
"Deluxe" line two way FM radios and the GE 1949 "Pre Progress
Line" two piece sets. The separate Selector Set was called the
106A. See below.

The decoders in these sets were capable of responding to a
maximum of five digits, and operated by a series of small pins placed in holes
around the circumference of a toothed ratchet wheel. As the operator dialed a
specific mobile unit, all the wheels in all of the mobile phones within range
would begin to move in step with the pulses being dialed from the telephone
company's base station. At the end of the first digit, only those mobiles with
pins in the wheels set to that number would hold the wheels at that spot. The
others would reset to the rest position. This process would continue through the
fifth digit, at which point (ideally) all the decoder wheels in the other mobile
phones would have returned to the rest position except the one whose five pins
matched the number dialed by the operator, at which point the wheel would close
a switch and the mobile's bell would ring. The signals from the telephone
company were audio tones, alternating between 600 and 1500 cycles as a digit was
dialed. It was possible to hear the stepper wheel operating in your trunk
with calls for other people, and even to anticipate when your phone would ring
by listening to the stepper ratcheting.

This first system of mobile telephony would come to be
referred to as "MTS." There were no dial facilities in the cars - - to
initiate a call, the push-to-talk button would be depressed briefly, which would
cause a lamp to light at the mobile operator's switchboard and put the base
station at the telephone company on the air. The mobile unit would give the
operator its telephone number and city of registry, and the desired number to be
dialed. The mobiles were not "duplex," i.e. operation of the handset
pushbutton was "push to talk," and "release to listen." The
majority of the mobile telephones had no squelch circuit, so the characteristic
FM "rushing" noise would emanate from the handset whenever the base
station went off the air. This was not a problem since the handset audio was
muted whenever it was hung up on its cradle.

Equipment manufactured by Motorola (the "Deluxe
Line") was also placed in service together with the Western Electric,
principally on the "Highway" channels, along with a small number of GE
two-piece FM transmitter-receivers (also for "Highway" service.)

Independent telephone companies utilized equipment nearly
identical to that of the first Western Electric car telephones, which was
manufactured by Automatic Electric Co. as shown below, and believed to have been
used with Motorola and GE radios:

MOTOROLA "DELUXE"
LINE ADAPTED FOR MTS USE:

The photo below shows a Bell System Motorola "Deluxe" line
high band ( 150 MHz) "Urban" radiotelephone installed in a taxicab in Delaware in
1948, taking up practically the entire trunk. Many of these units had a
sheet metal plate tack welded to the upper cabinet lid covering the connector
area. This was to keep the connectors and cables from being bashed to
pieces by things being thrown into the trunk, and were usually seen in taxicabs.

The
Type 106A rotary signaling selector unit is shown on the far right. The
receiver would have been a model FMRU-16V modified for Western Electric use and
(apparently) renumbered WERU-16-V (for a 6 Volt receiver.) The transmitter
would have been the WETU-30-D ( 6 Volt Urban dynamotor powered transmitter)
which in Motorola numbering was the FMTU-30D.

The cabinets on these units show that they have been "recycled" by the
Bell System already -- one is slightly older than the other and they don't
strictly match. These were regular two way radios modified for Bell System
use by incorporating the external selector unit and a telephone-like control
head.

In the picture below, the far left is the
receiver, the center the transmitter, and the far right the 106A Selector Set.

Notice that this guy should be shopping for a new spare
tire!

EARLY CAR TELEPHONES ON TV

There are assorted films and TV
shows which made use of the earliest mobile telephones. I hope to list them here
as they become known. In many cases only the handset is shown and it can
be assumed that there was no actual control head and only the
"prop" handset was used. But some show the entire control
head. Some movies, while attempting to feature car telephones, show only
complete props or other fakes. An example would be Sabrina,
starring Humphrey Bogart, which unfortunately shows only a fake mobile telephone
control head and a ridiculous gigantic antenna on the limousine it's mounted
in. Genuine early MTS car telephone sightings are listed below:

1) The Feb. 15, 1960 episode of
Peter Gunn, TV detective show, entitled "The Hunt," features the Type 41A control head
in Gunn's car, at approximate time hack 10:08 (depends on whether
this is the Hulu or YouTube version.) . Great view of the
control head.

A few other Peter Gunn episodes circa
1959-60 show him using an MTS mobile telephone as well, such as this one (you
can skip ahead to 20:40 if desired,) the January 4, 1960 episode entitled
"Hot Money:"